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Web scraping with Python [closed]
...utifulSoup(urllib2.urlopen('http://example.com').read())
for row in soup('table', {'class': 'spad'})[0].tbody('tr'):
tds = row('td')
print tds[0].string, tds[1].string
# will print date and sunrise
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How to count TRUE values in a logical vector
...values.
See for example:
z <- c(TRUE, FALSE, NA)
sum(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na.rm = TRUE) # best way to count TRUE values
(whi...
How would you count occurrences of a string (actually a char) within a string?
... found that Richard Watson's solution is fastest in most cases. That's the table with results of every solution in the post (except those use Regex because it throws exceptions while parsing string like "test{test")
Name | Short/char | Long/char | Short/short| Long/short | Long/long |
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NoSql Crash Course/Tutorial [closed]
...I'm really stuck in a relational-db mindset thinking of things in terms of tables and joins...
9 Answers
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How to calculate moving average using NumPy?
...inciple behind this answer is widely used in image processing (summed area tables they call it), so the issue had to be in the implementation. A good example of being bit by premature optimization, since I kind of recall doing the operation in-place "because it will be more efficient." On the bright...
How to write UPDATE SQL with Table alias in SQL Server 2008?
...ment on SQL Server is as follows:
UPDATE Q
SET Q.TITLE = 'TEST'
FROM HOLD_TABLE Q
WHERE Q.ID = 101;
The alias should not be necessary here though.
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Prevent jQuery UI dialog from setting focus to first textbox
...s>
In the documentation, the focus logic is explained (just under the table of contents, under the title 'Focus'):
Upon opening a dialog, focus is automatically moved to the first item
that matches the following:
The first element within the dialog with the autofocus attribute
T...
SQL Server 2008: how do I grant privileges to a username?
I need to be able to establish an ODBC connection through SQL Server authentication.
3 Answers
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When/Why to use Cascading in SQL Server?
...eal key rather than a surrogate key (identity/autoincrement column) across tables.
The canonical example for Cascade Update is when you have a mutable foreign key, like a username that can be changed.
You should not use Cascade Update with keys that are Identity/autoincrement columns.
Cascade Updat...
Do AJAX requests retain PHP Session info?
...session data, and it's possible that the main page request is locking that table, preventing the AJAX request from accessing it.
– Buttle Butkus
Aug 7 '19 at 3:57
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